The study is designed to measure serum and salivary CYFRA21-1 levels using enzyme linked immunosorbent assay (ELISA) in patients with oral malignancy, oral potentially malignant lesions, and control subjects to evaluate the potential of CYFRA21-1 as a diagnostic marker for malignant transformation in potentially malignant oral mucosal lesions.

Inclusion Criteria:

participants will be divided into 3 groups:

• Group I: patients suffering from oral potentially malignant lesions (PML) as defined by World Health Organization.
• Group II: patients suffering from diagnosed oral malignant lesions
• Group III: healthy subjects who are systemically free, non-smokers, and not suffering from any oral mucosal lesions.

Exclusion Criteria:

• Subjects taking any drugs inducing any changes that could affect the salivary flow.
• Pregnant females.
• Subjects have any allergies, infectious diseases or active dental abscesses during one month before saliva sampling.
• Patients receiving any drugs related to the oral lesions in the past 6 month prior to sample collection.

Egyptian population